Groundwater Flashcards
How many rounds of groundwater sampling is needed to demonstrate applicability of MNA?
Minimum of 8 rounds, four must be consecutive quarterly ground water monitoring events
Well types needed in an MNA network
Upgradient, Source, Plume Fringe, Sentinel well, likely need additional performance monitoring wells also (in the plume footprint)
When should your groundwater sample rounds for MNA start?
Can be historic from SI/RI when data reflects historic remediation or general attenuation. If there’s an active remedy, it must be AFTER the active remedy has ended and aquifer has had time to equillibrate.
What is Darcy’s Law?
GW Seepage velocity
Seepage Velocity = (hydraulic conductivity * hydraulic gradient)/effective porosity
What is this:
Vs=(Ki)/ne
Darcy’s Law
Seepage Velocity = (hydraulic conductivity * hydraulic gradient)/effective porosity
What’s the fall line?
Line from Trenton to Carteret (due to presence of waterfalls/rapids) that is the end of the Coastal Plain
Describe Coastal Plain Deposits
Early Cretaceous into Miocene, sand/silt/clay dipping towards the coast
Describe Glacial Sediment Deposits
Overly about 30% of state, lie between Phillipsburg to Perth Amboy, southern boundary is Plainfield
Varies from clay to boulder
Describe the Newark Basin
Largest physiographic province -(Piedmont) in the northern half of NJ. Non-marine sedimentary and igneous rocks of Triassic and early Jurassic.
Sandstone, siltstone, mudstone. Leaky multi-unit aquifer
Igneous rocks are basalt flows and diabase intrusion
Describe Ridge and Valley province
Paleozoic sedimentary bedrock including sandstone, shales, conglomerates, limestone and dolomite
Describe Crystalline Bedrock in NJ
Cambrian and Precambrian metamorphic and igneous of New England province.
Soil field screening techniques
Visual
Organic vapor monitors (PID, FID)
Soil Agitation Tests
UV Fluorescence (good for clear, colorless NAPL)
Hydrophobic Indicator Dyes (good for clear, colorless NAPL)
What does Caliper log (geophysical) teach us?
Bedrock investigation - tells casing depth/diameter, borehole diameter, and fracture zones
What does BIPS and AT (geophysical) tell us?
Fracture orientation, lithology, structural features and solution opening, casing depth, borehole orientation/deviation
What does Gamma (geophysical) tell us?
Lithology changes (eg. sandstone v shale), gamma marker beds for stratigraphic correlation to determine dip/strike of bedding